JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <div id="myQuestions">
        <select id="QuestionOptions">
            <option value disalbe selected>What Day is it?</option>
            <option value="A">Monday</option>
            <option value="A">Tuesday</option>
            <option value="B">Wednesday</option>
            <option value="B">Thursday</option>
            <option value="B">Friday</option>
            <option value="A">Saturday</option>
            <optoin value="A">Sunday</optoin>
        </select>
    </div>
    <div id="myAnswers">
            <div id="QuestionC">
                <p>Example of question.</p>
            </div>
            <div id="QuestionD">
                <select id="QuestionOptionsD">
                    <option value disalbe selected>Choose Your Answer</option>
                    <option id="AnsG" value="G">Answer G</option>
                    <option id="AnsH" value="H">Answer H</option>
                    <option id="AnsI" value="I">Answer I</option>
                    <option id="AnsJ" value="J">Answer J</option>
                </select>
            </div>
    </div>
</body>

JavaScript

var day = document.getElementById('QuestionOptions');
var ansG = document.getElementById('AnsG');
var ansH = document.getElementById('AnsH');
var ansI = document.getElementById('AnsI');
var ansJ = document.getElementById('AnsJ');

// set initial answer to none
ansI.style.display = ansJ.style.display = ansG.style.display = ansH.style.display = 'none';

day.addEventListener('change', function() {
	var QO = document.getElementById('QuestionOptions').selectedIndex;
	var val = document.getElementsByTagName("option")[QO].value;
  if(val === 'A') {
  	ansG.style.display = ansH.style.display = 'initial';
    ansI.style.display = ansJ.style.display = 'none';
  } else {
  	ansG.style.display = ansH.style.display = 'none';
    ansI.style.display = ansJ.style.display = 'initial';
  }
});